A fluffy, aromatic, and delicious almond cake filled with cinnamon pear filling and frosted with silky almond meringue buttercream.
Using nonstick spray, grease three 6-inch round cake pans or three 8-inch round cake pans. Line pan bottoms with parchment paper. Preheat oven to 350 degrees F.
In a medium bowl or measuring cup, combine egg whites, whole egg, 1/4 cup of the milk (the rest to be added later), almond and vanilla extracts. Set aside.
In the bowl of an electric mixer fitted with the paddle attachment (or using a hand mixer), combine all the dry ingredients together on low speed for 30 seconds.
Add the butter pieces one at a time, about every 10 seconds, ensuring it's kept cold. Continue to mix on low just until the mixture is a fine, crumbly texture. Add remaining milk, and mix on low speed for 4-5 minutes. Scrape the sides of the bowl and begin to add the egg mixture in 3 separate batches, mixing until light and fluffy, about 4 minutes. Fold once or twice to ensure the batter at the bottom is well incorporated.
Divide the batter evenly between the cake pans, spreading the tops gently until smooth.
Bake for about 30 minutes or until cake tester/toothpick comes out with only a few crumbs when inserted into the center. Begin checking cake at the 20 minute mark to avoid overbaking. Note: If baking in three 8-inch pans, cake may be done sooner.
Let cakes cool on wire rack for 10 minutes. Then, loosen sides with small metal spatula or butter knife and invert onto greased wire racks (I use cooking spray). Remove parchment paper and allow to cool completely.
Place chopped pears, sugar, lemon juice, cinnamon, nutmeg, and salt in medium saucepan. Stir gently and bring to a quick boil.
Decrease heat to medium-low and simmer uncovered for about 25 minutes or until pears are soft.
In a small bowl, combine warm water and cornstarch until dissolved. Add cornstarch mixture to pears in saucepan. Increase heat to high to bring to a boil. Boil for 30 seconds to thicken. Then, turn off and remove from heat. Allow to cool to room temperature before filling cake. If making filling ahead, cover and refrigerate up to 5 days.
Put the sugar and egg whites in a mixer bowl or another large heatproof bowl, fit the bowl over a pan of simmering water and whisk constantly, keeping the mixture over the heat, until it feels hot to the touch, about 5 minutes. The sugar should be dissolved, and the mixture will look like shiny marshmallow cream. Remove the bowl from the heat.
Working with the whisk attachment or with a hand mixer, beat the meringue on medium speed until it is cool, about 5-7 minutes. Switch to the paddle attachment if you have one, and add the butter a stick at a time, beating until smooth. Once all the butter is in, beat the buttercream on medium-high speed until it is thick and very smooth, 6-10 minutes. During this time the buttercream may curdle or separate – just keep beating and it will come together again.
On medium speed, add in almond and vanilla. Press a piece of plastic wrap against the surface of the buttercream bowl and set aside briefly (if not using right away).
Using a sharp serrated knife and a gentle sawing motion, slice the domed tops off of each cake layer. Place first layer cut side up on a cardboard cake round or a cake plate protected by strips of wax or parchment paper.
Using an offset spatula or a butter knife, lightly frost the top of the first cake layer with buttercream. Then, place some buttercream into a piping bag. Snip off the end and pipe a ring of buttercream in a circle along the outer edge of the cake, creating a dam. Fill center evenly with the fruit filling. I used about 1/2 cup between each layer.
Place second cake on top of of first later cut side up and repeat step 2. Place final third layer on top with cut side down. Press down gently on cake top.
Using a metal spatula, apply a thin layer of buttercream on top and sides of cake to create a crumb coat. Place in refrigerator for 15 -20 minutes to set. Remove from refrigerator and apply second buttercream coat. Smooth sides and top using metal spatula or pastry bench scraper. Place back in refrigerator for another 15-20 minutes.
Decorate with fondant cut-outs or pipe buttercream around cake edge using a star decorating tip set inside a piping bag.
If using dark gray or black cake pans, cake will bake faster. Reduce baking time accordingly.
If making a two tier stacked cake as I have, make sure to use supportive wooden dowels or smoothie straws (cut the same height as your bottom tier) in your bottom cake before placing the smaller one on top.